Electronic devices, such as notebook computers, are now being designed to operate with multi-media features such as those found in desktop units. In order for the user to have as enjoyable an experience as with desktops, the sound emanating from the notebook should present as full a harmonic content as the original sound. Most notebooks today currently are limited to not having frequencies generated below 150 Hz. Since most consumer audio equipment supports a frequency range of 20 Hz to 20 kHz, the full richness of the sound the user expects just is not present in notebook computers.
Notebook computers are limited in generating this low frequency content due to several factors. The first factor is that the space limitation in the product restricts how large a speaker may be used to replicate the sound. A second related factor is that lower frequencies need to move a large mass of air to be heard and there is little suitable volume in which to construct the air chamber that a speaker needs. A third factor is that due to the human ear's weak response to low frequency signals, more power is required to generate a lower frequency signal with an equivalent loudness compared to a signal greater than 150 Hz. More power reduces the battery life of the notebook computer or requires more expensive circuitry to implement than current designs.
Small electronic device makers such as notebook computer manufacturers or small handheld television producers continually fail to adequately provide a full, rich harmonic sound in their products.